When your hydraulic slide-out rooms stop responding or behave erratically, the MIRC (Multiple Input Relay Controller) is often the culprit. The Lippert 134800 is the OEM-matched replacement standard MIRC for 4-room hydraulic slide-out systems, designed to restore full, reliable room operation without modification or rewiring guesswork.
Lippert's hydraulic slide-out systems rely on the MIRC to coordinate room movement, interpret switch inputs, and manage the hydraulic pump relay logic for each slide-out room. When this module fails, rooms may refuse to extend or retract, move unevenly, or trigger false fault conditions. Replacing it with the correct OEM part number -- 134800 -- ensures your system returns to factory-spec behavior.
This is the standard MIRC variant, built for systems managing up to 4 slide-out rooms. It is a direct replacement unit and installs into the existing wiring harness without cutting or splicing when replacing a factory-installed Lippert MIRC of the same type.
Manages hydraulic relay logic for up to 4 individual slide-out rooms from a single control module.
Plug-in replacement for factory Lippert MIRC installations -- no harness modification required on matching systems.
Engineered specifically for Lippert hydraulic slide-out systems, not cable or electric motor slide variants.
Backed by Lippert's limited 1-year manufacturer warranty for defects in materials and workmanship.
The Multiple Input Relay Controller (MIRC) is the central logic board that receives commands from your slide-out wall switches and translates them into relay outputs that activate the hydraulic pump and directional solenoids for each room. Over time, MIRC units can fail due to voltage spikes, moisture intrusion, vibration fatigue, or simply age. Symptoms of a failing MIRC include:
Before replacing the MIRC, verify 12V power and a solid chassis ground are reaching the module, and confirm that individual room solenoids and the hydraulic pump themselves are not the source of the fault. A MIRC that receives no power or has a broken ground will appear dead even when healthy. That said, if power and ground check out and rooms still fail to respond, the MIRC is the most common failure point in these systems.
Replacement is generally straightforward for someone comfortable with 12V RV electrical work: